1. Field of the Invention
The present invention relates generally to quick connect couplings.
2. Description of the Prior Art
There are many previously known quick connect couplings which are designed for connection with a nipple having a radially inwardly extending annular recess formed about the nipple at a positioned spaced from its end. These previously known quick connect couplings typically comprise an elongated tubular and cylindrical housing having one end adapted to be slidably positioned over the nipple to a connected position.
A plurality of spherical retainers are contained within openings formed circumferentially around the body such that the body openings register with the nipple recess when the coupling is moved to its connected position. Furthermore, the spherical retainers are movable between an inner locked position and an outer unlocked position. In their inner locked position, a portion of each ball is positioned within the nipple recess thus locking the coupling and nipple together. Conversely, with the spherical retainers moved radially outwardly to their unlocked position, the nipple and coupling are freely slidable relative to each other.
These previously known quick connect couplings also include a locking ring disposed coaxially around the body. This locking ring is axially movable between a retracted and an extended position. A cam surface on the locking ring cooperates with the spherical retainers to urge the spherical retainers towards their inner locked position as the locking ring is moved from its retracted to its extended position.
Typically at least three and usually six or more spherical retainers are provided within the quick connect coupling in order to secure the coupling to the nipple. Furthermore, these previously known spherical retainers are typically circumferentially equidistantly spaced from each other.
Although many previously known quick connect couplings, particularly metallic quick connect couplings, are manufactured by conventional machining operations, quick connect couplings formed of synthetic materials, such as plastic, can be manufactured much more inexpensively than metallic quick connect couplings. It would be particularly advantageous to manufacture the quick connect coupling, i.e. the body and locking ring, by molding.
One problem, however, arises when the body of the quick connect coupling is manufactured by the previously known molding operations. In particular, in the previously known quick connect couplings, the body openings which contain the retainers are generally cylindrical in shape and extend in a radial direction with respect to the axis of the body. Consequently, assuming that the coupling body is manufactured from a two-piece mold and the coupling includes at least six retainers, at least four of the openings formed to the body to contain the retainers are formed along an axis oblique to the parting axis of the mold halves.
Since at least some of the housing openings are formed along an axis oblique to the parting axis of the mold halves, it is not possible to use a simple two-piece mold. Instead, more complex, and more expensive, insert molding techniques must be employed. Insert molding techniques, however, disadvantageously increase the overall cost of the molding process and thus the cost of the part.